Two-stroke internal combustion engines are used to power recreational vehicles such as snowmobiles. These engines may cause large amounts of vibration. In order to decrease the amount of vibration transferred from the engine to the frame of a snowmobile, such engines are secured to the frame of the snowmobile by engine mounts attached to the bottom of the engine with position-adjustable dampers placed between the engine mounts and the frame. The dampers absorb a portion of the vibration produced by the engine. However, such conventional engine mounts are relatively bulky in order to support the weight of the engine and therefore require additional space within the frame and also require appropriate space for technicians to position the adjustable dampers and fasten the engine mounts to the frame. Conventional engine mounts typically require additional space in the frame at the front and rear of the engine.
U.S. Pat. No. 6,651,768 now assigned to Bombardier Recreational Products Inc. which is incorporated herein by reference, describes an engine mount for snowmobile that can be used when space for the engine within a frame is limited and which is easily accessible from the side of the frame for assembly and repair. The engine mount disclosed consists of a plate attached to the bottom of an engine. The engine mount includes four hollow, cylindrical attachment portions extending transversely to the longitudinal direction of the snowmobile frame, each receiving a dampening mount. Fasteners are inserted through the frame to couple with the dampening mounts and cylindrical attachment portions in a direction that is transverse to the longitudinal direction of the frame. The configuration of the dampening mounts permits effective dampening of the engine vibrations especially in a direction transverse to the direction of forward travel of the vehicle. The engine mount disclosed reduces the required space for engine mounts and for access during production and repair activities. The attachment portions are formed with the plate as a unitary, one-piece element. The plate is rigidly attached to the bottom of the engine prior to assembly into the frame.
Although, providing a mounting plate having integrated attachment portions effectively reduces the space requirements for engine mounts, the plate must extend the width of the engine in order to be fastened to the frame such that the mounting plate is a large piece of metal added to the bottom of the engine. As such, the mounting plate increases the weight of the snowmobile.
Thus, there is a need for an engine mount that alleviates some of the drawbacks of prior engine mounts and preferably reduces the weight of the snowmobile.